Modalità di estrazione e tracce di lavorazione dell'allume sui monti della Tolfa

Alum is a material to be extracted with peculiar procedures by getting a deep cut in the mountain, adequately supported with props and armor. The traditional working tools remain in use until the permanent closure of Camerali’s factories in the mid nineteenth century, with the only innovative contribution of powder-loaded mines. The start of the construction site, made up of different professionals and efficient infrastructure, was followed by the installation of small groups of houses around the quarries and processing sites. The manufacturing processes are four: calcination, maceration, leaching and crystallization. In the territory of Allumiere were carried out targeted surveys, primarily aimed at the identification and documentation of production facilities in three areas located in the same district: in “località La Bianca”, “Le Cave Vecchie” and the site of the “Castagneto de Cinque Bottini “, where also some of the alum quarries have been localized.